Reduce variable names in code generation

[LeventErkok]

The code generator uses way too many variables than necessary, due to the single-static assignment form it generates. It also skips a whole bunch of variable names that designate constants, as those get inlined.

In practice this works OK, since gcc (or any other decent compiler) can detect short lived variables and get rid of them easily. However, it might be nice if we did this automatically for platforms where the compilers may not do these optimizations. (Otherwise, the frames generated for calls will be too large..)

[LeventErkok]

not necessarily a top concern. If this becomes a real issue, then we might want to generate C through Language.C or some such system for better support for static analysis/